1 /* 2 * Copyright (C) 2007 Atmel Corporation 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 as 6 * published by the Free Software Foundation. 7 */ 8 #include <linux/delay.h> 9 #include <linux/kdebug.h> 10 #include <linux/notifier.h> 11 #include <linux/sched.h> 12 #include <linux/hardirq.h> 13 14 enum nmi_action { 15 NMI_SHOW_STATE = 1 << 0, 16 NMI_SHOW_REGS = 1 << 1, 17 NMI_DIE = 1 << 2, 18 NMI_DEBOUNCE = 1 << 3, 19 }; 20 21 static unsigned long nmi_actions; 22 23 static int nmi_debug_notify(struct notifier_block *self, 24 unsigned long val, void *data) 25 { 26 struct die_args *args = data; 27 28 if (likely(val != DIE_NMI)) 29 return NOTIFY_DONE; 30 31 if (nmi_actions & NMI_SHOW_STATE) 32 show_state(); 33 if (nmi_actions & NMI_SHOW_REGS) 34 show_regs(args->regs); 35 if (nmi_actions & NMI_DEBOUNCE) 36 mdelay(10); 37 if (nmi_actions & NMI_DIE) 38 return NOTIFY_BAD; 39 40 return NOTIFY_OK; 41 } 42 43 static struct notifier_block nmi_debug_nb = { 44 .notifier_call = nmi_debug_notify, 45 }; 46 47 static int __init nmi_debug_setup(char *str) 48 { 49 char *p, *sep; 50 51 register_die_notifier(&nmi_debug_nb); 52 53 if (*str != '=') 54 return 0; 55 56 for (p = str + 1; *p; p = sep + 1) { 57 sep = strchr(p, ','); 58 if (sep) 59 *sep = 0; 60 if (strcmp(p, "state") == 0) 61 nmi_actions |= NMI_SHOW_STATE; 62 else if (strcmp(p, "regs") == 0) 63 nmi_actions |= NMI_SHOW_REGS; 64 else if (strcmp(p, "debounce") == 0) 65 nmi_actions |= NMI_DEBOUNCE; 66 else if (strcmp(p, "die") == 0) 67 nmi_actions |= NMI_DIE; 68 else 69 printk(KERN_WARNING "NMI: Unrecognized action `%s'\n", 70 p); 71 if (!sep) 72 break; 73 } 74 75 return 0; 76 } 77 __setup("nmi_debug", nmi_debug_setup); 78